Optical discs such as compact discs (CDs), video compact discs (VCDs) and digital versatile disc (DVDs) are played via disc drives. When an optical pickup head of an optical disc drive operates, the light emitted by a light source such as a laser diode is focused by an object lens of the optical pickup head on an optical disc, and the light reflected by the optical disc is transmitted to a light sensor to realize information from the disc.
The disc loading/ejecting mechanisms of an optical disc reading apparatus are generally classified as three major types: a tray-loading mechanism, a top-loading mechanism and a slot-loading mechanism, as shown in FIGS. 1(a)˜1(c), respectively.
Referring to FIG. 1(a), a tray-loading mechanism is illustrated. For loading an optical disc to be read, a tray 10 is manually pulled out or mechanically transmitted out from the front of the disc drive 1. After the optical disc is positioned in the tray 10, the tray 10 is pushed back inside the disc drive 1 for reading operations. Likewise, when the disc is to be unloaded, the tray 10 extends forwards and out of the housing 11 again to allow the disc to be removed. According to this tray-loading mechanism, it is required to reserve an operative space in front of the disc drive sufficient for the extension of the tray 10 for loading/ejecting the disc.
In the top-loading mechanism of FIG. 1(b), for loading an optical disc to be read, the top lid 111 of the housing 11 is lifted upwards. After the disc is positioned, the top lid 111 is put down to cover the disc and the reading operation can be performed. Likewise, when the disc is to be unloaded, the top lid 111 is lifted upwards again to allow the disc to be removed from the disc drive 1. In this top-loading mechanism, an operative space above the disc drive 1 is required for uplifting the top lid 111 to load/eject the disc.
Referring to FIG. 1(c), a slot-loading mechanism is illustrated. The disc drive 1 has a slot 12 in a front panel thereof for receiving therein a disc. When the disc drive 1 detects that a disc at the entrance of the slot 12, a transmitting mechanism inside the disc drive 1 will automatically transmit the disc inwards. Since the disc is front-loaded, an operative space in front of the disc drive is still needed for loading/ejecting the disc, which is similar to the case of FIG. 1(a).
In views of the spatial restriction, the above disc loading mechanisms need further improvement.